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Combining Domains and Linear Constraints
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<H2 CLASS="section"><A NAME="htoc239">17.1</A>&nbsp;&nbsp;Combining Domains and Linear Constraints</H2>
Most optimisation problems arising in industry and commerce involve
different subproblems that are best addressed by different algorithms
and constraint solvers. In ECL<SUP><I>i</I></SUP>PS<SUP><I>e</I></SUP> it is easy to use different
constraint solvers in combination. The different solvers may share
variables and even constraints.<BR>
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We discuss reasons for combining the <TT>eplex</TT> and <EM>IC</EM> solver libraries and explore ways of doing this. The <TT>repair</TT>
library plays a useful role in propagating solutions generated by a
linear solver to other variables handled by the domain solver.
We show how this works in a generic hybrid algorithm termed <EM>probing</EM>.<BR>
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